The CRE pledge

Labour: 269 of 417 MPs signed Tory: 55 of 160 signed, 3 refused Lib Dem: 45 of 47 signed Others: 9 signed

He accused party leader William Hague of not doing enough to stamp out racism among members - but the Conservatives accused him of a "grotesque misrepresentation" of the facts.

The Commission for Racial Equality (CRE) pledge, already signed by the three main party leaders, is designed to ensure a racism-free general election.

The group has named retiring backbencher John Townend, former minister Eric Forth and party whip James Cran as the three Tory MPs who have declined to sign it.

But Mr Gummer said making the MPs' names public risked implying that they were racist.

"The CRE seems to me to be using a measure of blackmail in this way which is unacceptable."

Mr Gummer insisted it was not racist to avoid signing the pledge

He went on: "The problem is that at every election people ask you to sign a whole series of things of this sort. This is wholly unconstitutional because your relationship is with your constituents.

"Now I've got a long record of fighting racism so no one can accuse me of being a racist, but I want my constituents to ask me the questions that they care about and discuss with me on any subject they like."

Mr Gummer, who served as agriculture minister from 1989 to 1993, said he objected neither to the wording of the pledge nor to the party leaders signing it.

But when pressed he declined to say whether he would be signing the document.

"I have to draw a line otherwise I am being asked as a constituency candidate to sign up to all kinds of issues under an implied threat," he added.

Free speech

Mr Gummer's comments were backed by fellow Tory MP Sir Richard Body who said: "If we are going to have various bodies requiring people to sign declarations of one kind or another there could be really no end to it."

Dr Raj Chandran, a former member of the CRE and Conservative candidate at the 1997 general election, said the pledge was counter-productive and risked suppressing freedom of speech.

In a speech on Thursday night Mr Cook hailed the "gathering of countless different races and communities" in modern day Britain.

He sugested that chicken tikka masala could be given a new status as the national dish and went on to attack recent statements from the Tory leadership.

"In the last few months they have warned that Britain is in the process of becoming 'a foreign land', that we are being 'flooded' by asylum seekers and that foreign doctors are putting the lives of British patients at risk.

"If William Hague really wants to stamp out racism in his party, he should lead by example," said Mr Cook.

Race card

Mr Hague insisted it was reasonable to raise the legitimate concerns of voters, particularly over the asylum system.

"It's not racist to say that, it's nothing to do with any racist attitude," the Tory leader said.

"It's simply saying that when we have rules they should be properly enforced, that this country should be a safe haven for people fleeing persecution but not a soft touch."

Tory chairman Michael Ancram attacked Mr Cook's speech as "a vicarious way of playing the race card which I think is quite ridiculous and should be condemned".

Liberal Democrat home affairs spokesman Simon Hughes said Mr Hague had given a "green light" to more racist attitudes in his party but Labour were not guiltless either.